Recently, in some geographical areas, there has been a growing concern regarding the use of phosphorus-containing compounds in laundry detergent compositions because of some evidence that links such compounds to the eutrophication of lakes and streams. While it is not clear whether or not this link is really significant, some governmental bodies have begun to restrict the phosphorus content of detergent compositions, necessitating the formulation of laundry detergents containing chelants less effective than the conventionally-used phosphonates or polyphosphonates. These requirements have complicated the formulation of effective and appropriately priced laundry detergent compositions. It would, therefore, be highly desirable to be able to formulate detergent compositions substantially free of peroxygen or chlorine bleach compounds which contain reduced levels of phosphorous-containing components, but still exhibit excellent cleaning and stain removal performance.
Accordingly, it is an object of the present invention to provide novel detergent compositions which exhibit improved stain and soil removal characteristics.
It is another object of the present invention to provide novel laundry detergent compositions substantially free of peroxygen or chlorine bleach compounds which still exhibit excellent cleaning and stain removal performance.
It is another object of the present invention to provide novel laundry detergent compositions substantially free of peroxygen or chlorine bleach compounds which exhibit excellent cleansing and stain removal performance, particularly under harsh water conditions.
It is a final object of the present invention to provide novel laundry detergent compositions which contain PEI's, as nil-phosphorous chelants.
These and other objects of the invention will be more readily apparent in the description that follows.
The use of PEI sequestrants in various compositions are generally disclosed in the art.
U.S. Pat. No. 3,033,746 to Moyle et al. discloses compositions comprising PEI for use in coating, oil/latex paint and cellulosic applications. The compositions are said to have improved antimicrobial properties by combining halophenol compounds with PEI.
WO 94/27621 to Mandeville discloses a method of reducing iron absorption from the gastrointestinal tract by orally administering a therapeutic amount of PEI.
U.S. Pat. No. 4,085,060 to Vassileff discloses sequestering compositions for industrial applications comprising polycarboxylate polymers and PEI which have excellent sequestering properties for metals.
U.S. Pat. No. 3,636,213 to Gerstein discloses a method for solubilizing heavy metal salts of 1-hydroxy-2-pyridinethione in cosmetic formulations where PEI functions as a solubilizing agent.
U.S. Pat. No. 3,400,198 to Lang discloses wave set retention shampoo compositions containing PEI. The compositions are said to precipitate on the hair fiber when diluted with water in the course of usage. Upon drying, PEI improves the wave retention of the hair as well as improving hair manageability. No builders or enzymes are present in such compositions.
U.S. Pat. No. 3,740,422 to Hewitt and U.S. Pat. No. 3,769,398 to Hewitt disclose aqueous and aqueous alcoholic scalp rinses containing solubilized PEI. It is said that PEI is effective against Pityrosporum ovale, the fungus believed to be associated with dandruff and therefore PEI serves as an anti-dandruff agent. No builders or enzymes would be present in such compositions.
British Patent No. 1,524,966 (to Reckitt and Colman Products) and British Patent No. 1,559,823 (to Reckitt and Colman Products) disclose anti-dandruff shampoo compositions comprising PEI as a conditioning agent for hair and as an antimicrobial agent. Again, no detergency builders or enzymes would be present in such compositions.
U.S. Pat. No. 5,360,581 to Rizvi et al. and U.S. Pat. No. 5,417,965 to Janchitraponvej et al. disclose conditioning shampoo compositions containing PEI. It is said that protonated PEI's with cationic polyquaternium 32 provide improved stability and conditioning benefits. No detergency builders or enzymes would be present in such compositions.
U.S. Pat. No. 3,251,778 to Dickson et al., U.S. Pat. No. 3,259,512 to Dickson et al. and U.S. Pat. No. 3,271,307 to Dickson et al. disclose processes for preparing PEI's and derivatives thereof. It is suggested that PEI's can be broadly used in various applications such as oil well treatment, asphalt applications, textile applications and the like.
U.S. Pat. No. 5,259,984 to Hull discloses a rinse free cleaner composition for hands, upholstery and carpet containing PEI.
U.S. Pat. No. 2,182,306 to Ulrich, U.S. Pat. No. 2,208,095 to Esselmann, U.S. Pat. No. 2,553,696 to Wilson, U.S. Pat. No. 2,806,839 to Crowther and U.S. Pat. No. 3,627,687 to Teumac et al. disclose methods of preparing various PEI's.
U.S. Pat. No. 3,844,952 to Booth discloses detergent and fabric softener compositions containing alkylated and alkanoylated PEI's as antistatic agents. The alkylated or alkanoylated polyethyleneimines disclosed by Booth differ structurally from the polyethyleneimines and polyethyleneimine salts (or mixtures) of the invention which are not derivatized.
Furthermore, there are numerous patents that describe various alkoxylated derivatives of PEI (similar to those described by Booth) which are also structurally very different and are otherwise unrelated to the present invention. See for example, U.S. Pat. Nos. 2,792,372, 4,171,278, 4,341,716, 4,597,898, 4,561,991, 4,664,848, 4,689,167 and 4,891,160.
Finally, perhaps the most relevant references that do disclose the use of polyethyleneimines in detergent compositions are as follows.
U.S. Pat. No. 3,489,686 to Parran, for example, discloses detergent compositions containing certain PEI's which serve to enhance deposition and retention of particulate substances an surfaces washed with such compositions. There is no teaching or suggestion that polyethyleneimines be used in compositions substantially free of enzymes.
AU Patent No. 17813/95 (to Procter & Gamble) and JP 08,053,698 (to Procter & Gamble) disclose detergent compositions containing 0.01% to 10% PEI substantially free of tertiary amino groups having a specific molecular weight of 100-600 as a polymeric chlorine scavenger. The compositions are said to minimize fading of fabric colors sensitive to chlorine which may be present in the composition or in the wash or rinse water. The compositions optionally contain peroxygen or chlorine bleaching agents.
Once again compositions of the subject invention are free of peroxygen or chlorine bleach compounds, include builders and enzymes, and provide excellent cleansing and stain removal characteristics without bleaching action, even under harsh wash water conditions.
Accordingly, none of the above patents or applications disclose the improved compositions of the present invention or recognize the unique fabric stain removal properties of PEI or PEI salts (or mixtures thereof) in the context of laundry detergent compositions substantially free of bleach.